1. Field of the Invention
The invention relates to a seating furniture component or the like, especially an upholstered furniture component with coupled backrest and seat adjustment including such sittable reclining furniture as, for example, an upholstered recliner with height-adjustable back part, or a corresponding hospital bed. More specifically, the invention relates to such an upholstered furniture component having a support chassis with a backrest adjustably attached to the support chassis and with a seat adjustable attached to the support chassis, backrest and seat being movably joined to one another in the area of the vertex of the angle between them, the backrest being coupled to a pivot axis on the support chassis at a distance above the vertex of the angle, and the seat being movably attached near the front edge by means of a support mechanism on the support chassis so that the backrest executes a superimposed tiltback and lowering motion from the highest upright position, i.e., the sitting position, into the lowest extended position, i.e., the reclining position, relative to the support chassis and the seat executing slight motion in a synchronized manner from the sitting position to the reclining position, preferably, a superimposed sliding and lifting motion.
2. Description of Related Art
Variously comfortable and complex seating furniture components (armchair, upholstered armchair, easy chair, bus, railroad and aircraft seats, reclining furniture with height adjustable back part), especially upholstered furniture components in which the backrest adjustment and seat adjustment are coupled are known from the prior art. International Application Publication WO 95/25452, which forms the starting point of this invention, provides a good outline of the generally known prior art.
First of all, a seating furniture component is known in which the backrest with the seat forms an angularly-rigid unit which is attached to the support frame to pivot around a pivot axis under the seat such that the backrest tilts back and down when leaning backwards into the reclining position, while the seat swings down at its back end and up at its front end (FIGS. 1 & 2 of WO 95/25452). This movement is normally produced against the force of a return spring. Here, the angularly-rigid connection of the backrest and seat adjustment is uncomfortable, and there is no extended position of the backrest and seat. In addition, it is uncomfortable that the front edge of the seat is moved considerably upward in the reclining position, not being especially salubrious to the legs of the user.
A construction of a seating furniture component is relatively common in which the support chassis is made frame-like with the backrest being pivotally joined to the rear part of the frame-like support chassis a considerable distance above the coupling point of the backrest to the rear edge of the seat (FIGS. 3 & 4 of WO 95/25452). The rear edge of the seat is thus supported by means of the backrest on the support chassis. On or near the front edge, the seat is guided in a slide guide which has only a slight upward tilt, so that the front edge of the seat moves forward, but only slightly upward during the transition from the sitting position into the reclining position.
In the aforementioned system, a user can move into different positions between the sitting position and reclining position relatively easily and without expending a large amount of force by shifting his body weight. However, it is generally necessary to use an additional braking means to be able to maintain a certain desired position.
One disadvantage in the seating furniture component is the result of the pivoting connection of the backrest and the seat roughly at the peak of the angle of the two components. The connection of the two components is structurally simple, but the two components generally carry upholstered supports. The upholstered surfaces of the upholstered supports used by the user are somewhat above the seat or in front of the backrest and thus somewhat above or in front of the pivot axis between the backrest and seat. This results in the fact that, in the transition from the sitting position into the reclining position, the upholstered supports move away from one another results in a so-called "shirt pullout effect" which the user perceives as very unpleasant.
Another problem which is likewise the result of the aforementioned pivot connection at the angle vertex is a "hole" which forms in the pelvis/back area in the transition from the sitting position into the reclining position. This "hole" is disruptive when it is too large, since the pelvis/flank area is then no longer properly supported in the reclining position.
Finally, the attachment of the seat to the front edge must be carefully done so that an overly great blow into the hollows of the knee of the user does not occur in the transition from the sitting position into the reclining position.
Attempts have already been made in the prior art to eliminate the "shirt pullout effect" by providing a connection mechanism, between the backrest and the seat in the area of the rear edge or lower edge, which places the axis of the pivot connection between the backrest and seat, roughly where the surfaces of the two upholstered supports abut one another in the sitting position. This is done by flaps which project on the edge side from the respective frame and which are joined to pivot with one another only on their free ends (FIGS. 5 & 6 of WO 95/25452).
In other seating furniture component, a major advantage is gained over the above-mentioned known seating furniture components by the coupling point of the backrest to the support chassis being located, not above the coupling point of the backrest to the seat, but far below it. This is also done via a lever mechanism, a knee joint connection accomplishing an additional superimposed tilting motion of the backrest. The seat itself is joined to pivot near its front edge on the support chassis at a considerable distance from the coupling point of the backrest to the support chassis. Since this coupling point is near the front edge of the seat, the front edge of the seat, in the transition from the sitting into the reclining position, is raised less than in the seating furniture components known from the prior art.
Analysis of the above explained, known seating furniture component has shown that, as before, the "shirt pullout effect" is noticeable when a relatively extended reclining position is desired. The position change shown in FIGS. 5 and 6 of WO 95/25452 illustrates that only a relatively small tiltback motion of the backrest is possible if a comparatively strong "shirt pullout effect" is to be avoided. In addition, the "hole" in the pelvis/back area is still too large. Finally, the embodiment of the above explained prior art (FIGS. 5, 6), in any case, shows that major lifting of the front edge of the seat takes place. This may be acceptable for a seat with footrests, but this is not the case for a seating furniture component of the type under consideration which generally has no foldable footrest.